Tuning gastropod locomotion: Modeling the influence of mucus rheology on the cost of crawling

Common gastropods such as snails crawl on a solid substrate by propagating muscular waves of shear stress on a viscoelastic mucus. Producing the mucus accounts for the largest component in the gastropod's energy budget, more than twenty times the amount of mechanical work used in crawling. Using a simple mechanical model, we show that the shear-thinning properties of the mucus favor a decrease in the amount of mucus necessary for crawling, thereby decreasing the overall energetic cost of locomotion.Comment: Corrected typo

Populasi Dan Serangan Penggerek Daun (Phyllocnistis Citrella Staint) Pada Tanaman Jeruk Dan Alternatif Pengendaliannya

Observation on population and attack of meneerder (PDJ) and its natural enemies was conducted since Julyto September 2002 in Winowanga village, Lore Utara district, and Poso regency, Central Sulawesi, at 1,200 m abovesea level. This study aimed to evaluate population and attack of PDJ and its natural enemy to set an integrated pestmanagement (IPM) program on citrus. Observation was conducted at the four models of cropping patterns as thetreatments and three location as the replication using a randomized block design. Average population of the pest was2.75 rear/plant and rate of attack was of 19 percent. Natural enemies\u27 population of the large black ant in thecropping pattern of Arjuna corn variety with local tomato variety among citrus plants was 2.1 heads/plant and that ofspider was 2.0 heads/plant. In the Cropping patern of corn with kidney bean local variety among citrus plants theaverage population of this pest was 1.66 heads/plant and rate of attack was 20.83 percent on the leaves. Naturalenemies\u27 population of the large black ant was 1.50 heads/plant and that of spider was 1.70 heads/plant. In thecropping pattern of corn among citrus plants the average population of this pest was 1.33 heads/plant and rate ofattack was 9.16 percent. Natural enemyies\u27 population of the large black ant was 130 heads/plant and that of spiderwas 1.40 heads/plant. In the citrus monoculture cropping pattern the average population of this pest was 2.0 was/plantand rate attack was 18.66 percent. Natural enemies\u27 population of the large black ant was 1.60 heads/plant and that ofspider was 1.90 heads/plant. These cropping patterns could increase farmers\u27 income and could be classified as IPMcomponents as long as pests monitoring is carried out every five days.Key words : phylocnistis citrella, population, rate of attack, citrus Pengamatan populasi dan serangan penggerek daun jeruk (PDJ) telah dilaksanakan sejak bulan Juli sampaiSeptember 2002 di Desa Winowanga, Kecamatan Lore Utara, Kabupaten Poso Sulawesi tengah, pada ketinggian 1200m di atas permukaan laut. Pengamatan bertujuan untuk mengetahui populasi PDJ dan musuh alami serta seranganhama tersebut pada tanaman jeruk, sebagai dasar untuk menyusun program pengendalian hama terpadu PDJ.Pengamatan dilakukan pada empat model pola tanam sebagai perlakuan dan tiga lokasi sebagai ulangan. Data-datadari hasil pengamatan tersebut kemudian dianalisis menggunakan rancangan kelompok. Hasil pengamatanmenunjukan bahwa populasi dan serangan PDJ beserta musuh alami pada empat pola tanam tersebut adalah sebagaiberikut : (1) Pola tanam jagung varietas Arjuna dengan tomat varietas lokal diantara tanaman jeruk varietas keprok.Rata-rata populasi hama tersebut adalah 2,75 ekor/tanaman dan serangan 19 persen. Musuh alami semut hitam danlaba-laba masing-masing sekitar 2 ekor/tanaman; (2) Pola tanam jagung dan kacang merah varietas lokal diantaratanaman jeruk varietas keprok. Rata-rata populasi hama PDJ adalah 1,6 ekor/tanaman dan serangan 20,0 persen.Musuh alami jenis Dolichoderus sp rata-rata 1,5 ekor/tanaman dan laba-laba 1,7 ekor/tanaman; (3) Pola tanam jagungvarietas arjuna diantara jeruk varietas keprok. Rata-rata populasi hama PDJ 1,3 ekor/tanaman dan serangan sekitar19,0 persen. Musuh alami Dolichoderus sp 1,30 ekor/tanaman dan laba-laba 1,4 ekor/tanaman; (4) Monokultur jeruk.Rata-rata populasi PDJ 2,0 ekor/tanaman dan serangan 18,0 persen. Musuh alami Dolichoderus sp 1,60 ekor/tanamandan laba-laba 1,9 ekor/tanaman. Model pola tanam tersebut dapat meningkatkan pendapatan petani dan dapattergolong komponen-komponen PHT, dengan syarat monitoring hama harus dilakukan intensif setiap lima hari gunamembatasi serangan hama tersebut

Tradable Permits

Tradable Permits – a Market-Based Allocation System for the Environment. Tradable Permits and Other Environmental Policy Instruments – Killing one Bird with two Stones. Tradable Permits – Ten Key Design Issues. Tradable Permits with Imperfect Monitoring. Emissions Trading with Greenhouse Gases in the European Union.Umweltzertifikat, Umweltökonomik, Immissionsschutz, Umweltpolitik, Klimaschutz, EU-Umweltpolitik, Wirtschaftspolitische Wirkungsanalyse, EU-Staaten, Vereinigte Staaten, Environmental economics, Emission control, Environmental policy, Climate protection, EU environmental policy, Economic policy analysis, EU countries, United States

Effects of vibrational energy relaxation and reverse reaction on electron transfer kinetics and fluorescence line shapes in solution

The existing theoretical formulations of electron transfer reactions (ETR) neglect the effects of vibrational energy relaxation (VER) and do not include higher vibrational states in both the reactant and the product surfaces. Both of these aspects can be important for photo-induced electron transfer reactions, particularly for those which are in the Marcus inverted regime. In this article, a theoretical formulation is presented which describes the two aspects. The formalism requires an extension of the hybrid model introduced earlier by Barbara et al. [Science 256, 975 (1992)]. We model a general electron transfer as a two-surface reaction where overlap between the vibrational levels of the two surfaces create multiple, broad reaction windows. The strength and the accessibility of each window is determined by many factors. We find that when VER and reverse transfer are present, the time dependence of the survival probability of the reactant differs significantly (from the case when they are assumed to be absent) for a large range of values of the solvent reorganization energy (λX), quantum mode reorganization energy (λq), electronic coupling constant (Vel) and vibrational energy relaxation rate (kVER). Several interesting results, such as a transient rise in the population of the zeroth vibrational level of the reactant surface, a Kramers (or Grote-Hynes) type recrossing due to back reaction and a pronounced role of the initial Gaussian component of the solvation time correlation function in the dynamics of electron transfer reaction, are observed. Significant dependence of the electron transfer rate on the ultrafast Gaussian component of solvation dynamics is predicted for a range of values of Vel, although dependence on average solvation time can be weak. Another result is that, although VER alters relaxation dynamics in both the product and the reactant surfaces noticeably, the average rate of electron transfer is found to be weakly dependent on kVER for a range of values of Vel; this independence breaks down only at very small values of Vel. In addition, the hybrid model is employed to study the time resolved fluorescence line shape for the electron transfer reactions. It is found that VER can have a significant influence on the fluorescence spectrum. The possibility of vibrational state resolved spectra is investigated

SMART BRT ITERA Management: A Pilot Project of Indonesia's Inclusive Bus Campus System

Sustainable transportation service is not only about reducing exhaust emissions but about its impact on society.This work seeks to analyze the potential of ITERA Smart Bus Rapid Transit (Smart BRT ITERA) as a regional campus buses in creating the accessibility needed by the wider community, affordable in terms of tariffs, efficient and supporting economic development and reducing emissions and waste generated in the Institut Teknologi Sumatera (ITERA) in Lampung, Indonesia. As a commitment to sustainability by planning Smart BRT ITERA form of collaboration with the Ministry of Transportation of the Republic of Indonesia. ITERA, in this case, acts as the operator of 10 buses grants by the Ministry to serve this activity. It is hoped that this project can become a best practice for other universities in Indonesi

Hubungan Komunikasi Interpersonal Tenaga Pendamping dengan Partisipasi Petani dalam Program Aksi Desa Mandiri Pangan (Proksi Demapan) di Kelurahan Pall Merah Kota Jambi

Ketahanan pangan adalah kondisi terpenuhinya pangan bagi rumah tangga yang tercermin dari tersedianya pangan yang cukup, baik jumlah maupun mutunya, aman, merata dan terjangkau. Salah satu upaya mengatasi masalah kerawanan pangan dan kemiskinan adalah melalui Program Aksi Desa Mandiri Pangan. Penelitian ini bertujuan untuk mengetahui tingkatan pelaksanaan komunikasi interpersonal yang digunakan tenaga pendamping dalam Program Aksi Desa Mandiri Pangan di Kelurahan Pall Merah Kota Jambi serta untuk mengetahui hubungan antara komunikasi interpersonal tenaga pendamping dengan partisipasi petani dalam Program Aksi Desa Mandiri Pangan di Kelurahan Pall Merah Kota Jambi. Pemilihan lokasi dilakukan secara purposive dilatar belakangi karena Kelurahan Pall Merah telah mengikuti Program Aksi Desa Mandiri Pangan pada tahun 2010 hingga sekarang telah mencapai tahap kemandirian dan kondisi perkembangan dana bantuan sosial cukup tinggi di antara Kelurahan lainnya yang mengikuti program tersebut. Jenis data dalam penelitian ini meliputi data primer dan sekunder. Data dianalisis secara deskriptif melalui tabel distribusi frekuensi. Uji analisis yang digunakan adalah uji dengan metode Chi-Square (χ2). Dari hasil penelitian diperoleh bahwa : 1) Komunikasi interpersonal yang digunakan tenaga pendamping kategori tinggi sebesar 45%, sedang sebesar 35% dan rendah sebesar 20%. Hal ini menunjukan komunikasi interpersonal yang digunakan tenaga pendamping dalam program Aksi Desa Mandiri Pangan efektif. 2) Terdapat hubungan yang erat antara komunikasi interpersonal tenaga pendamping dengan partisipasi petani dalam Program Aksi Desa Mandiri Pangan di Kelurahan Pall Merah Kota Jambi

Karakteristik Keinovatifan Petani Padi Sawah dan Hubungannya dengan Tingkat Partisipasi dalam Kelompok Tani

Keberhasilan pembangunan pertanian tidak dapat dipisahkan dari peran serta petani sebagai pelaku utama dalam melaksanakan kegiatan USAhataninya, yang berarti petani berperan langsung dalam pembangunan pertanian. Oleh karena itu keberhasilan program Pembangunan Pertanian ditentukan oleh partisiasipasi petani itu sendiri. Penelitian ini akan menelaah hubungan karakteristik keinovatifan petani padi sawah dengan tingkat partisipasinya dalam kelompok tani. Adapun tujuan penelitian ini adalah untuk mengetahui tingkat keinovatifan petani dan tingkat partisipasinya dalam kelompok tani serta untuk mengetahui hubungan antara kedua variabel tersebut. Dalam hal ini karaktersitik keinovatifan petani dirasakan sangat penting karena karakteristik keinovatifan petani merupakan faktor yang mempengaruhi tingkat partisipasinya dalam kelompok tani. Semakin tinggi tingkat karakteristik keinovatifan petani maka akan semakin tinggi pula tingkat partisipasinya dalam kelompok tani. Hasil uji Korelasi Rank Spearman pada taraf nyata α = 0,01 untuk melihat apakah ada hubungan antara karakteristik keinovatifan petani dengan tingkat partisipasinya dalam kelompok tani, ternyata menyatakan hubungan yang nyata dimana = 0,803 yang artinya berhubungan sangat kuat dan memiliki arah hubungan yang positif. Sedangkan tingkat karakteristik keinovatifan petani padi sawah di Desa Sri Agung Kecamatan Tanjung Jabung Barat secara keseluruhan tergolong dalam kategori sedang dengan jumlah persentase sebesar 56 % dari jumlah 50 sampel dan tingkat partisipasi petani juga termasuk dalam kategori sedang dengan jumlah persentase 54 %